On a recent visit to Berkeley I was given the chance to take a stab at assembling a stained glass piece. To be clear, I wasn't staining/coloring the glass myself, though I have done that back when I had access to the materials science glass blowing shop. The first step was to choose a design, and given my background I chose a rather suspect flower. Next the glass was picked out at a local stained glass craft shop near the bay; a bright blue, a purple, a green, and a reddish-purple provided all the colors I'd need. All said and done, about $20 worth of glass. Next we printed the design and outlined and numbered the obvious segments, and with a pair of three-bladed scissors (designed to remove a narrow strip of paper from between the segments to allow for solder and copper tape) cut out all the segments.
The next step was to take each segment, keeping track of the color it was supposed to be, and gluing it down to the appropriate glass using an middle-school style glue stick. Each bit of glass was then broken out into the approximate shape of the segment using a glass scorer and pliers. Then came the grinding. The grinder sported a metal grinding post with a constant feed of water to keep the dust and heat down, and proved to be the most fun part of the entire process as there was little to no risk of breaking the pieces. After each piece had been ground to a more-or-less perfect shape, the segments were re-assembled into the original shape to check their fit. A few places had to be re-ground, but overall it came together nicely.
Now that we were convinced that the pieces all fit well, we were able to wash away the paper and finally see the design in the colors we picked out earlier in the day. The challenge here was to keep everything in order, as the pieces now had no identifying features and could easily be confused for similarly shaped pieces.
A bit of materials science wisdom comes into play here. Glass and metal rarely play well together, and soda-lime glass and solder are no exception. In order to get the solder to effectively glue the segments together an intermediate metal has to be applied to the edges of the segments. Copper tape, being a strip of copper with adhesive on one side, serves this purpose beautifully. Each piece of glass had a stripe of tape straddling it's edge such that the edge and a few millimeters on both sides were covered. You'll notice in the photo below that two of the petals on the left had to be broken into two parts as they broke during cutting, but the visual impact of this is quite minimal. I attribute this to my poor choice of shapes during the initial drawing process, as I didn't think about how easily the shapes could be realized.
With everything taped, the remaining steps were to solder the pieces together, patina the solder to a darker color, and protect the whole thing with wax. Having soldered before this was an easy process, the only non-intuitive part of which was tapping. Tapping refers to dropping little blobs of solder around at key points to lock the pieces in a single orientation before trying to fill the gaps in a continuous manner.
A quick rinse with flux remover left the surface clean. The patina, with plenty of labels reminding us that it is very toxic, was quick acting and gave the solder a nice pewter look. Lastly the liquid wax was rubbed onto both sides, and the whole thing was washed in soap and water to remove any excess flux, patina, and wax to make it safe the handle.
An early flight left me without a good source of packing materials the morning I flew back to Tucson, so I trusted that my portfolio was sturdy enough to protect the piece for a few hours. When I got home I discovered that it apparently wasn't good enough; several cracks had formed in the central pieces. They were not enough to compromise the piece, and it should hold together for some time while looking awesome in my window.
